The Moon’s orbit around the Earth is inclined by about 5 degrees from the plane of the Earth’s orbit around the Sun, so only occasionally does the Moon come between the Earth and the Sun so as to cause a solar eclipse. The diameter of the Moon as viewed from the Earth is about the same as the apparent diameter of the Sun, so the Moon can just barely cover the whole disk of the Sun. Because the Moon’s orbit around the Earth is elliptical, most of the time when there is a solar eclipse, is only partial. It is only when the Moon is closest to the Earth that the Moon can completely block out the Sun and cause complete darkness for a few minutes of totality

As the diagram below indicates, the zone of total eclipse, where the Sun is completely blocked, is very small. Only about one in…